1 /* 2 * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 12 /* 13 * This header file includes the VAD API calls. Specific function calls are given below. 14 */ 15 16 #ifndef WEBRTC_COMMON_AUDIO_VAD_INCLUDE_WEBRTC_VAD_H_ // NOLINT 17 #define WEBRTC_COMMON_AUDIO_VAD_INCLUDE_WEBRTC_VAD_H_ 18 19 #include "webrtc/typedefs.h" 20 21 typedef struct WebRtcVadInst VadInst; 22 23 #ifdef __cplusplus 24 extern "C" { 25 #endif 26 27 // Creates an instance to the VAD structure. 28 // 29 // - handle [o] : Pointer to the VAD instance that should be created. 30 // 31 // returns : 0 - (OK), -1 - (Error) 32 int WebRtcVad_Create(VadInst** handle); 33 34 // Frees the dynamic memory of a specified VAD instance. 35 // 36 // - handle [i] : Pointer to VAD instance that should be freed. 37 void WebRtcVad_Free(VadInst* handle); 38 39 // Initializes a VAD instance. 40 // 41 // - handle [i/o] : Instance that should be initialized. 42 // 43 // returns : 0 - (OK), 44 // -1 - (NULL pointer or Default mode could not be set). 45 int WebRtcVad_Init(VadInst* handle); 46 47 // Sets the VAD operating mode. A more aggressive (higher mode) VAD is more 48 // restrictive in reporting speech. Put in other words the probability of being 49 // speech when the VAD returns 1 is increased with increasing mode. As a 50 // consequence also the missed detection rate goes up. 51 // 52 // - handle [i/o] : VAD instance. 53 // - mode [i] : Aggressiveness mode (0, 1, 2, or 3). 54 // 55 // returns : 0 - (OK), 56 // -1 - (NULL pointer, mode could not be set or the VAD instance 57 // has not been initialized). 58 int WebRtcVad_set_mode(VadInst* handle, int mode); 59 60 // Calculates a VAD decision for the |audio_frame|. For valid sampling rates 61 // frame lengths, see the description of WebRtcVad_ValidRatesAndFrameLengths(). 62 // 63 // - handle [i/o] : VAD Instance. Needs to be initialized by 64 // WebRtcVad_Init() before call. 65 // - fs [i] : Sampling frequency (Hz): 8000, 16000, or 32000 66 // - audio_frame [i] : Audio frame buffer. 67 // - frame_length [i] : Length of audio frame buffer in number of samples. 68 // 69 // returns : 1 - (Active Voice), 70 // 0 - (Non-active Voice), 71 // -1 - (Error) 72 int WebRtcVad_Process(VadInst* handle, int fs, const int16_t* audio_frame, 73 int frame_length); 74 75 // Checks for valid combinations of |rate| and |frame_length|. We support 10, 76 // 20 and 30 ms frames and the rates 8000, 16000 and 32000 Hz. 77 // 78 // - rate [i] : Sampling frequency (Hz). 79 // - frame_length [i] : Speech frame buffer length in number of samples. 80 // 81 // returns : 0 - (valid combination), -1 - (invalid combination) 82 int WebRtcVad_ValidRateAndFrameLength(int rate, int frame_length); 83 84 #ifdef __cplusplus 85 } 86 #endif 87 88 #endif // WEBRTC_COMMON_AUDIO_VAD_INCLUDE_WEBRTC_VAD_H_ // NOLINT 89
